Among his various speculations while at Willington, he tried to discover a means of Perpetual Motion. Although he failed, as so many others had done before him, the very efforts he made tended to whet his inventive faculties and to call forth his dormant powers. He actually went so far as to construct the model of a machine for the purpose. It consisted of a wooden wheel, the periphery of which was furnished with glass tubes filled with quicksilver; as the wheel rotated, the quicksilver poured itself down into the lower tubes, and thus a sort of self-acting motion was kept up in the apparatus, which, however, did not prove to be perpetual. Where he had first obtained the idea of this machine--whether from conversation, or reading, or his own thoughts, is not known; but his son Robert was of opinion that he had heard of an apparatus of this kind as described in the "History of Inventions." As he had then no access to books, and, indeed, could scarcely yet read, it is probable that he had been told of the invention, and set about testing its value according to his own methods. Much of his spare time continued to be occupied by labor more immediately profitable, regarded in a pecuniary point of view. In the evenings, after his day's labor at his engine, he would occasionally employ himself for a few hours in casting ballast out of the collier ships, by which means he was enabled to earn a few shillings weekly. Mr. William Fairbairn, of Manchester, has informed the author that, while Stephenson was employed at the Willington Ballast Hill, he himself was working in the neighborhood as an engine apprentice at the Percy Main Colliery. He was very fond of George, who was a fine, hearty fellow, besides being a capital workman. In the summer evenings young Fairbairn was accustomed to go down to Willington to see his friend, and on such occasions he would frequently take charge of George's engine for a few hours, to enable him to take a two or three hours' turn at heaving ballast out of the ships' holds. It is pleasant to think of the future President of the British Association thus helping the future Railway Engineer to earn a few extra shillings by overwork in the evenings, at a time when both occupied the rank but of humble working men in an obscure northern village. Mr. Fairbairn was also a frequent visitor at George's cottage on the Quay, where, though there was no luxury, there was comfort, cleanness, and a pervading spirit of industry. Even at home George was never for a moment idle. When there was no ballast to heave, he took in shoes to mend; and from mending he proceeded to making them, as well as shoe-lasts, in which he was admitted to be very expert. William Coe, who continued to live at Willington in 1851, informed the author that he bought a pair of shoes from George Stephenson for 7_s._ 6_d._, and he remembered that they were a capital fit, and wore very well.